Krochmal was largely an autodidact. In addition to German, French, and Latin, he taught himself medieval Jewish philosophy and Kabbalah, including the thought of Avraham ibn Ezra, Maimonides, and Naḥmanides; European philosophy, especially that of Spinoza, Kant, Schelling, and Hegel; and contemporary biblical criticism, especially the work of Johann Gottfried Eichhorn. He also studied historical texts, such as those of ‘Azaryah dei Rossi and Isaac Marcus Jost, and classical rabbinic sources—such as the Palestinian Talmud and various midrashic collections—that went beyond the traditional Jewish education he received in Brody.

During his lifetime, Krochmal published very little; instead, he devoted much of his time to his roles as community leader and businessman, the latter to support his wife and four children. Still, he developed a reputation as a great scholar and maskil, and many traveled to Żółkiew to study with him, often by taking long walks with him to the surrounding hills to discuss philosophy, history, and Jewish law and lore. Others relied on the mail to raise their questions and concerns. The early decades of the nineteenth century were not an easy time for those associated with the Haskalah, and Krochmal experienced considerable tension in his dealings with the dominant traditional communities of Galicia.

Krochmal’s lasting fame is based on his posthumously published and unfinished magnum opus, the Moreh nevukhe ha-zeman (the Guide of the Perplexed of the Time; 1851), brought to press by Leopold Zunz. As the title implies, it is an effort to update Maimonides’ classic work so as to address the perplexities of the post-Enlightenment age; the title may also be meant to imply that the book would serve as a guide to those perplexed by time in the sense of history, as much of the text is devoted to showing how Judaism can emerge unscathed—albeit not unchanged—from its encounter with historicization.

The work consists of 17 chapters, the first 7 of which are devoted to brief statements of Krochmal’s guiding philosophies of religion and history; chapters 8 though 10 set forth the basic patterns of Jewish history. Chapter 11 presents Krochmal’s approach to biblical criticism; chapter 12 describes ancient Alexandrian Jewish culture, especially the works of Philo; and chapters 13 and 14 analyze the emergence of the classical rabbinic tradition. The next two chapters are fragments devoted to early Jewish gnosticism and to concepts and definitions necessary for an understanding of Jewish metaphysics (largely culled from the works of Hegel). The final chapter presents central Jewish metaphysical doctrines—which Krochmal attributed to Avraham ibn Ezra, but which in many ways are closer to kabbalistic forms of Jewish Neoplatonism, many of which bear striking resemblance to nineteenth-century idealist philosophy. As the book contains no real introduction, one can only speculate as to the ways in which the author saw all this material coming together to coherently guide those perplexed by the modern age.

Some things are clear, however. Krochmal, basing himself on Kantian and Hegelian epistemological concepts, regarded religion as a form of philosophy, more primitive in expression but not in substance. Thus, the challenge for the contemporary interpreter of religious texts was to discern the underlying philosophical message, and to refine it. When one does this properly with Judaism, Krochmal believed, one discovers a sophisticated conception of God and God’s interaction with the world that can stand up to the Enlightenment and Idealist criticisms of Judaism as theologically juvenile. For Krochmal, once one had properly decoded the imagery and rhetoric of Jewish religious sources, one would discover that the Jewish conception of God corresponded to the Absolute Spirit of Hegelian philosophy, encompassing within itself all reality.

This recognition of the absolute nature of God had important historical ramifications in Krochmal’s thought, as it allowed the Jewish nation, he maintained, to defy one of the “laws” of history that applied to all other cultures. In the various philosophies of history of the eighteenth and early nineteenth centuries, it was a commonplace that the lives of national cultures mirrored the lives of individual organisms, moving from birth and early development to maturation and then to decay and disappearance. Krochmal agreed with those who insisted that the vitality of national cultures was directly related to the cultures’ spiritual content; when that content was spent—in the sense that its creative impulses had ossified—the culture would cease to exist as an independent entity, even as its central spiritual dimensions might live on in other cultures. All other cultures, he argued, achieved only a partial relationship to Spirit, and thus were unable to sustain their vitality over time. But although the Jewish people underwent the same threefold cycle of birth, maturation, and decline as other peoples, unlike others—by virtue of its special relationship with the Absolute—the Jewish people did not disappear but was reborn, to go through the cycle again and again. Krochmal reviews the periods of Jewish history to demonstrate empirically that Jews had already gone through three full cycles and were in his lifetime at the dawn of yet a fourth, with their cultural vitality intact.

Much of Krochmal’s work, in fact, was designed to demonstrate the continuing cultural and religious vitality of the Jews through the distinct cycles of their history. Toward this end, Krochmal turned his attention especially to the Bible, rabbinic literature, and medieval philosophy and Kabbalah; he argued that each body of literature attests in its own way to the fact that Jewish cultural creativity remained at high levels—perhaps increasingly elevated levels—throughout time.

It is in these reflections on the emergence and quality of Jewish literatures that Krochmal’s most lasting contribution is to be found. The chapter on the Bible in Moreh nevukhe ha-zeman establishes him as one of the early Jewish pioneers of biblical criticism anywhere, and perhaps the first such in Eastern Europe. While never questioning the divine origin of the Pentateuch, Krochmal shares the views of Europe’s most important biblical critics regarding certain biblical books. He insists that the book of Isaiah as we have it consists of the prophecies of two prophets; that Ecclesiastes could not have been written by Solomon but must date to long after the Babylonian exile of the sixth century BCE; and that many Psalms could not have been written by David—some of them date, in his view, to as late as the Maccabean period (second century BCE). He also briefly extends his critical view to other books, among them Daniel and Zechariah. True to his traditionalist tendencies, Krochmal insists that classical rabbis already knew the truth about these books, and communicated that truth in esoteric fashion. Thus, none of his critical claims regarding this literature need challenge traditional beliefs, and the dating of books later than was commonly accepted by those who relied on the exoteric traditions demonstrated the continuous vitality of Jewish culture.

Similarly, Krochmal’s influential reconstruction of the emergence of rabbinic tradition rhetorically upholds traditional categories, especially the notion of an Oral Torah. He also introduces historical categories to produce a portrait that was quite conservative by comparison with German Reform historiography, but was quite daring by the standards of East European Orthodoxy. Drawing on the insights of the German legal historian Friedrich Karl von Savigny, Krochmal insists that all legal systems are the product of lengthy periods of oral transmission of customary practice that eventually find their way into legal codes. Thus, Rabbinic Judaism is very much a product of oral tradition, even if it is not as conventionally understood. This tradition, Krochmal argues, emerged over many centuries, supervised first by the sofrim, or scribes, who defined critical terms, and then by the tana’im, who began to examine the logic of the written Torah and who created extensions of law in keeping with that logic; they subsequently established the connection of these laws to scripture by an exegetical method Krochmal called midrash halakhah (a coinage that has become standard throughout the world of rabbinic scholarship). Krochmal goes on to historicize the emergence of the Mishnah and Gemara, explaining how each emerged in time against the backdrop of the political and intellectual developments of their respective ages. The resulting portrait was of a historical tradition rooted in hoary antiquity but endowed with the vigor to renew itself through time.

Krochmal’s other studies were to prove less influential, although his discussion on the nature of rabbinic agadah found some response. All of his works combined to fill out a portrait of Krochmal as a Jewish polymath deeply committed to the scholarly reconstruction of Jewish history in a way that was sympathetic to traditional Jewish self-understanding while remaining true to proper standards of independent intellectual investigation.

Krochmal’s influence was great throughout enlightened and scholarly circles in Eastern Europe (as well as Germany) right into the twentieth century; Mikhah Yosef Berdyczewski referred to him as “the source of wisdom from which Jewish scholars in the East must draw.” But arguably his greatest influence, like Moses Mendelssohn’s, may have derived not from his written works but from the personal example he set. In combining encyclopedic interests with extraordinary learning and scrupulous religious commitment, Krochmal served as an example of a religious figure who could confront the disorienting perplexities of the modern age and emerge with his religious commitment and scholarly integrity intact.